JP2786095B2 - Method for producing cerium carbonate and cerium oxide - Google Patents
Method for producing cerium carbonate and cerium oxideInfo
- Publication number
- JP2786095B2 JP2786095B2 JP5293169A JP29316993A JP2786095B2 JP 2786095 B2 JP2786095 B2 JP 2786095B2 JP 5293169 A JP5293169 A JP 5293169A JP 29316993 A JP29316993 A JP 29316993A JP 2786095 B2 JP2786095 B2 JP 2786095B2
- Authority
- JP
- Japan
- Prior art keywords
- cerium
- carbonate
- oxide
- cerium carbonate
- alkaline earth
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F17/00—Compounds of rare earth metals
- C01F17/20—Compounds containing only rare earth metals as the metal element
- C01F17/247—Carbonates
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Inorganic Chemistry (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Description
【０００１】[0001]
【産業上の利用分野】アルカリ土類金属不純物を低減し
た高純度炭酸セリウム及び酸化セリウムの製造方法に関
する。The present invention relates to a method for producing high-purity cerium carbonate and cerium oxide with reduced alkaline earth metal impurities.
【０００２】[0002]
【従来の技術】アルカリ土類金属不純物を低減させた希
土類炭酸塩を得るには、粗製希土類酸化物を鉱酸水溶液
に溶解し、アルカリ土類金属の沈殿の生成し難い酸性領
域で希土類金属を蓚酸塩として沈殿させ、それを焼成し
て酸化物とした後、塩酸、硝酸等の鉱酸に再溶解させて
炭酸塩として沈殿させる方法が一般的である。しかし、
セリウムの場合はその酸化物が鉱酸に溶解し難いため、
この方法は非常に生産性が悪くなる。またイオン交換法
や溶媒抽出法等でも希土類元素とアルカリ土類元素の分
離は可能であるが製造コストが高価になるのが欠点であ
る。2. Description of the Related Art To obtain a rare earth carbonate with reduced alkaline earth metal impurities, a crude rare earth oxide is dissolved in a mineral acid aqueous solution, and the rare earth metal is dissolved in an acidic region where precipitation of the alkaline earth metal is difficult to occur. It is a general method to precipitate as an oxalate, bake it to form an oxide, and then redissolve in a mineral acid such as hydrochloric acid or nitric acid to precipitate as a carbonate. But,
In the case of cerium, its oxide is difficult to dissolve in mineral acids,
This method is very productive. Further, the separation of the rare earth element and the alkaline earth element can be performed by an ion exchange method, a solvent extraction method, or the like, but has a disadvantage in that the production cost is high.
【０００３】[0003]
【発明が解決しようとする課題】本発明の目的はアルカ
リ土類金属不純物を低減した炭酸セリウムならびに酸化
セリウムを安価にしかも容易に提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide inexpensively and easily cerium carbonate and cerium oxide with reduced alkaline earth metal impurities.
【０００４】[0004]
【課題を解決するための手段】本発明者等はかかる課題
を解決するために、炭酸セリウムの生成条件を根本的に
見直した結果、特定pH条件下に生成することを見出し、
諸条件を確立して本発明を完成させたもので、その要旨
は、セリウム鉱酸塩水溶液のpHを 2.0〜 5.0に保持しな
がら炭酸根を有する化合物を投入し、反応させることを
特徴とする炭酸セリウムの製造方法にあり、更に詳しく
は、生成した炭酸セリウム（酸化セリウム換算）中のア
ルカリ土類金属不純物がセリウム鉱酸溶液（酸化セリウ
ム換算）中のそれの 1/2以下である炭酸セリウムの製造
方法及びこの炭酸セリウムを 250℃以上の温度で焼成す
る酸化セリウムの製造方法にある。Means for Solving the Problems The present inventors have fundamentally reviewed the conditions for producing cerium carbonate in order to solve such problems, and as a result, have found that cerium carbonate is produced under specific pH conditions.
The present invention has been completed by establishing various conditions, and the gist of the invention is characterized in that a compound having a carbonate group is added while maintaining the pH of the cerium mineral salt aqueous solution at 2.0 to 5.0, and the reaction is performed. A method for producing cerium carbonate; more specifically, cerium carbonate in which the amount of alkaline earth metal impurities in the produced cerium carbonate (in terms of cerium oxide) is less than half that in a cerium mineral acid solution (in terms of cerium oxide) And a method for producing cerium oxide by firing this cerium carbonate at a temperature of 250 ° C. or higher.
【０００５】以下、本発明を詳細に説明する。安価にし
かも容易にアルカリ土類金属不純物を低減した炭酸セリ
ウムおよび酸化セリウムを得る方法を検討した結果、セ
リウム炭酸塩を生成させる際に、セリウム鉱酸水溶液に
炭酸アンモニウム、炭酸水素アンモニウム等の炭酸根を
添加し、その時のpHを 2.0〜 5.0、好ましくは3.5 〜4.
5 に調整することにより生成セリウム炭酸塩（酸化セリ
ウム換算）中のアルカリ土類金属不純物がセリウム鉱酸
塩水溶液（酸化セリウム換算）中のそれの 1/2以下に低
減することが判った。セリウム鉱酸水溶液としては硝酸
セリウム、塩酸セリウム等が使用でき、これらは炭酸セ
リウムや水酸化セリウムを硝酸や塩酸で分解させたもの
を用いることができるがこれらに限定されるものではな
い。また前記炭酸根として好ましくは炭酸アンモニウ
ム、炭酸水素アンモニウムが挙げられるが、他にも炭酸
ガスとアンモニア水の混合物、アルカリ金属が不純物と
して許容される場合には炭酸ナトリウム、炭酸水素ナト
リウム等アルカリ金属炭酸塩等を利用することも可能で
あり、ここに挙げた化合物に限定されるものではない。
沈殿生成時のpHが 5.0を越えると急激に沈殿に取り込ま
れるアルカリ土類金属量が増加し目的を達成できない。
セリウム鉱酸塩水溶液のセリウム濃度は0.01〜2.0 mol/
L 、炭酸根はセリウムの 0.6〜 0.9倍当量が適量で 0.6
倍未満では未反応セリウムが損失となり、0.9倍を越え
ると生成炭酸セリウム中のアルカリ土類金属不純物量が
増加する。ここで当量とは、炭酸セリウムの沈殿生成に
必要な炭酸根量であり、鉱酸が過剰に存在した場合、中
和に必要な炭酸根は含まれない。本発明により得られた
精製炭酸セリウム中のアルカリ土類金属不純物量を更に
低減させる必要のある場合には、本発明精製操作を繰り
返せば達成できる。本発明で低減の対象となるアルカリ
土類金属はＭg 、Ｃa 、Ｓr 、Ｂa である。Hereinafter, the present invention will be described in detail. As a result of examining a method of obtaining cerium carbonate and cerium oxide with reduced alkaline earth metal impurities at low cost and easily, when producing cerium carbonate, a carbonate solution such as ammonium carbonate and ammonium hydrogen carbonate was added to a cerium mineral acid aqueous solution. , And the pH at that time is 2.0 to 5.0, preferably 3.5 to 4.
By adjusting to 5, it was found that the alkaline earth metal impurities in the produced cerium carbonate (in terms of cerium oxide) were reduced to less than half of those in the cerium mineral salt aqueous solution (in terms of cerium oxide). As the cerium mineral acid aqueous solution, cerium nitrate, cerium hydrochloride and the like can be used, and those obtained by decomposing cerium carbonate or cerium hydroxide with nitric acid or hydrochloric acid can be used, but are not limited thereto. Preferred examples of the carbonate group include ammonium carbonate and ammonium hydrogencarbonate. In addition, when a mixture of carbon dioxide gas and aqueous ammonia is acceptable as an alkali metal as an impurity, sodium carbonate, sodium hydrogencarbonate and other alkali metal carbonates may be used. It is also possible to use salts and the like, and it is not limited to the compounds listed here.
When the pH at the time of precipitation generation exceeds 5.0, the amount of alkaline earth metal taken into the precipitate rapidly increases, and the object cannot be achieved.
The cerium concentration of the cerium mineral salt aqueous solution is 0.01 to 2.0 mol /
L, carbonate is 0.6-0.9 times equivalent of cerium and 0.6
If it is less than twice, unreacted cerium is lost, and if it exceeds 0.9 times, the amount of alkaline earth metal impurities in the produced cerium carbonate increases. Here, the equivalent is the amount of carbonate necessary for precipitation of cerium carbonate, and does not include the carbonate necessary for neutralization when a mineral acid is present in excess. When it is necessary to further reduce the amount of alkaline earth metal impurities in the purified cerium carbonate obtained by the present invention, this can be achieved by repeating the purification operation of the present invention. The alkaline earth metals to be reduced in the present invention are Mg, Ca, Sr and Ba.
【０００６】アルカリ土類金属不純物の少ない酸化セリ
ウムは、上記方法によって製造された炭酸セリウムを常
法により 250℃以上の温度で焼成すれば良く、炭酸セリ
ウムと同様にアルカリ土類金属不純物がセリウム鉱酸塩
水溶液中のそれの1/2 以下のものが得られる。250 ℃未
満では焼成が不十分となり、未分解炭酸セリウムが残存
することになる。Cerium oxide having a small amount of alkaline earth metal impurities can be obtained by calcining the cerium carbonate produced by the above method at a temperature of 250 ° C. or more by a conventional method. Less than 1/2 of that in the aqueous acid salt solution is obtained. If the temperature is lower than 250 ° C., the sintering becomes insufficient and undecomposed cerium carbonate remains.
【０００７】[0007]
【実施例】以下、本発明の実施態様を実施例を挙げて具
体的に説明するが、本発明はこれらに限定されるもので
はない。 （実施例１）アルカリ土類金属不純物としてＣa がＣa
／Ｃe Ｏ2 ＝100ppm存在する硝酸セリウム水溶液（Ｃe
濃度0.6mol/dm3、［Ｈ+ ］=0.1mol/dm3 ）１dm3 を３dm
3 ビーカに入れ撹拌機で撹拌しながら炭酸水素アンモニ
ウム水溶液（２mol/dm3 ）をpHが 5.0を越えないように
徐々に添加し炭酸セリウムの沈殿を生成させた。0.9dm3
添加してpHが 5.0に到達したところで添加を終了した。
得られた炭酸セリウムスラリーを濾過し２dm3 の純水で
洗浄した後、乾燥して炭酸セリウムを得た。収率は90％
であった。得られた炭酸セリウム中のＣa を ICP法にて
分析したところＣa ／Ｃe Ｏ2 ＝10 ppmであった。ここ
で得られたセリウム炭酸塩をアルミナ坩堝に充填し大気
雰囲気下 500℃で焼成し酸化セリウムを得た。得られた
酸化セリウム中のＣa を ICP法にて分析したところＣa
／Ｃe Ｏ2 ＝ 10ppmであった。EXAMPLES Hereinafter, embodiments of the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. (Example 1) Ca is Ca as an alkaline earth metal impurity
/ CeO 2 = 100 ppm cerium nitrate aqueous solution (CeO 2
Concentration 0.6 mol / dm 3 , [H + ] = 0.1 mol / dm 3 ) 1 dm 3 to 3 dm
An ammonium bicarbonate aqueous solution (2 mol / dm 3 ) was gradually added to the mixture in a 3 beaker while stirring with a stirrer so that the pH did not exceed 5.0, to thereby precipitate cerium carbonate. 0.9dm 3
The addition was terminated when the pH reached 5.0 after the addition.
The obtained cerium carbonate slurry was filtered, washed with 2 dm 3 of pure water, and dried to obtain cerium carbonate. 90% yield
Met. When Ca in the obtained cerium carbonate was analyzed by ICP method, it was found that Ca / CeO 2 = 10 ppm. The obtained cerium carbonate was filled in an alumina crucible and calcined at 500 ° C. in the atmosphere to obtain cerium oxide. The Ca in the obtained cerium oxide was analyzed by ICP method.
/ CeO 2 = 10 ppm.
【０００８】（実施例２）アルカリ土類金属不純物とし
てＢa がＢa ／Ｃe Ｏ2 ＝100ppm存在する硝酸セリウム
水溶液（Ｃe 濃度0.6mol/dm3、［Ｈ+ ］=0.1mol/dm3 ）
１dm3 を３dm3 ビーカに入れ撹拌機で撹拌しながら炭酸
水素アンモニウム水溶液（２mol/dm3 ）をpHが 5.0を越
えないように徐々に添加し炭酸セリウムの沈殿を生成さ
せた。0.9dm3添加してpHが 5.0に到達したところで添加
を終了した。得られた炭酸セリウムスラリーを濾過し２
dm3 の純水で洗浄した後、乾燥して炭酸セリウムを得
た。収率は90％であった。得られた炭酸セリウム中のＣ
a を ICP法にて分析したところＢa ／Ｃe Ｏ2 ＝ 20ppm
であった。ここで得られたセリウム炭酸塩をアルミナ坩
堝に充填し大気雰囲気下 500℃で焼成し酸化セリウムを
得た。得られた酸化セリウム中のＢa を ICP法にて分析
したところＢa ／Ｃe Ｏ2 ＝ 20ppmであった。(Example 2) Cerium nitrate aqueous solution containing Ba as an alkaline earth metal impurity (Ba / CeO 2 = 100 ppm) (Ce concentration: 0.6 mol / dm 3 , [H + ] = 0.1 mol / dm 3 )
1 dm 3 was placed in a 3 dm 3 beaker, and an aqueous solution of ammonium hydrogen carbonate (2 mol / dm 3 ) was gradually added while stirring with a stirrer so that the pH did not exceed 5.0, thereby causing precipitation of cerium carbonate. The addition was terminated when 0.9 dm 3 was added and the pH reached 5.0. The obtained cerium carbonate slurry was filtered and filtered.
After washing with pure water of dm 3 and drying, cerium carbonate was obtained. The yield was 90%. C in the obtained cerium carbonate
a was analyzed by the ICP method to find that Ba / CeO 2 = 20 ppm
Met. The obtained cerium carbonate was filled in an alumina crucible and calcined at 500 ° C. in the atmosphere to obtain cerium oxide. When Ba in the obtained cerium oxide was analyzed by ICP method, it was found that Ba / CeO 2 = 20 ppm.
【０００９】（比較例１）実施例１と同量の硝酸セリウ
ム水溶液に炭酸水素アンモニウム水溶液を徐々に添加し
て炭酸セリウムの沈殿を生成させ、液のpHが 7.0になる
まで1.0dm3添加した。得られた炭酸セリウムスラリーを
濾過し２dm3 の純水で洗浄した後、乾燥して炭酸セリウ
ムを得た。収率は98％で、炭酸セリウム中のＣa を ICP
法にて分析したところＣa ／Ｃe Ｏ2 ＝ 90ppmであっ
た。Comparative Example 1 An aqueous solution of ammonium bicarbonate was gradually added to an aqueous solution of cerium nitrate in the same amount as in Example 1 to form a precipitate of cerium carbonate, and 1.0 dm 3 was added until the pH of the solution became 7.0. . The obtained cerium carbonate slurry was filtered, washed with 2 dm 3 of pure water, and dried to obtain cerium carbonate. Yield is 98%. Ca in cerium carbonate is converted to ICP
Analysis by the method showed that Ca / CeO 2 = 90 ppm.
【００１０】（比較例２）実施例１と同じ硝酸セリウム
水溶液および炭酸水素アンモニウム水溶液を用いて投入
法を代えて行った。まず３dm3 ビーカに炭酸水素アンモ
ニウム水溶液0.9dm3入れ撹拌機で撹拌しながら硝酸セリ
ウム溶液を徐々に添加し炭酸セリウムの沈殿を生成させ
た。得られた炭酸セリウムスラリーを濾過し2dm3の純水
で洗浄した後、乾燥して炭酸セリウムを得た。得られた
炭酸セリウム中のＣa を ICP法にて分析したところＣa
／Ｃe Ｏ2 ＝ 95ppmであった。(Comparative Example 2) Using the same cerium nitrate aqueous solution and ammonium hydrogen carbonate aqueous solution as in Example 1, the charging method was changed. First was 3dm 3 beaker gradually generate the added precipitation of cerium carbonate to cerium nitrate solution with stirring bicarbonate aqueous ammonium 0.9Dm 3 Put stirrer. The obtained cerium carbonate slurry was filtered, washed with 2 dm 3 of pure water, and dried to obtain cerium carbonate. The Ca in the obtained cerium carbonate was analyzed by ICP method.
/ CeO 2 = 95 ppm.
【００１１】[0011]
【発明の効果】本発明によれば、安価にしかも容易にア
ルカリ土類金属不純物を低減した炭酸セリウム及び酸化
セリウムを得ることが出来、産業上その利用価値は極め
て高い。According to the present invention, cerium carbonate and cerium oxide with reduced alkaline earth metal impurities can be easily obtained at low cost, and their industrial value is extremely high.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) C01F 17/00──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. 6 , DB name) C01F 17/00
Claims (3)
保持しながら炭酸根を有する化合物を投入し、反応させ
ることを特徴とする炭酸セリウムの製造方法。1. A method for producing cerium carbonate, which comprises introducing a compound having a carbonate group and causing a reaction while maintaining the pH of the cerium mineral salt aqueous solution at 2.0 to 5.0.
算）中のアルカリ土類金属不純物量がセリウム鉱酸溶液
（酸化セリウム換算）中のそれの 1/2以下である請求項
１に記載の炭酸セリウムの製造方法。2. The cerium carbonate according to claim 1, wherein the amount of the alkaline earth metal impurities in the formed cerium carbonate (in terms of cerium oxide) is not more than 1/2 of that in the cerium mineral acid solution (in terms of cerium oxide). Manufacturing method.
酸セリウムを 250℃以上の温度で焼成する酸化セリウム
の製造方法。3. A method for producing cerium oxide, wherein the cerium carbonate obtained by the method according to claim 1 or 2 is calcined at a temperature of 250 ° C. or higher.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5293169A JP2786095B2 (en) | 1993-11-24 | 1993-11-24 | Method for producing cerium carbonate and cerium oxide |
| EP94118251A EP0654445A1 (en) | 1993-11-24 | 1994-11-19 | Method for the preparation of cerium carbonate powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5293169A JP2786095B2 (en) | 1993-11-24 | 1993-11-24 | Method for producing cerium carbonate and cerium oxide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07144915A JPH07144915A (en) | 1995-06-06 |
| JP2786095B2 true JP2786095B2 (en) | 1998-08-13 |
Family
ID=17791313
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5293169A Expired - Fee Related JP2786095B2 (en) | 1993-11-24 | 1993-11-24 | Method for producing cerium carbonate and cerium oxide |
Country Status (2)
| Country | Link |
|---|---|
| EP (1) | EP0654445A1 (en) |
| JP (1) | JP2786095B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100463799B1 (en) * | 2001-12-26 | 2004-12-29 | 한국지질자원연구원 | A method for manufacturing of cerium carbonate from the cerium hydroxide |
| WO2005026051A1 (en) | 2003-09-12 | 2005-03-24 | Hitachi Chemical Co., Ltd. | Cerium salt, process for producing the same, cerium oxide, and cerium-based abrasive material |
| CN100391847C (en) * | 2005-04-05 | 2008-06-04 | 内蒙古包钢稀土高科技股份有限公司 | RE salt preparing process and apparatus |
| US8361419B2 (en) | 2005-09-20 | 2013-01-29 | Lg Chem, Ltd. | Cerium carbonate powder, method for preparing the same, cerium oxide powder made therefrom, method for preparing the same, and CMP slurry comprising the same |
| KR100786961B1 (en) * | 2005-09-20 | 2007-12-17 | 주식회사 엘지화학 | Cerium carbonate powder, method for preparing the same, cerium oxide powder made therefrom, method for preparing the same, and cmp slurry comprising the same |
| KR100812052B1 (en) | 2005-11-14 | 2008-03-10 | 주식회사 엘지화학 | Cerium carbonate powder, cerium oxide powder, method for preparing the same, and cmp slurry comprising the same |
| KR100986881B1 (en) | 2007-03-16 | 2010-10-08 | 주식회사 엘지화학 | Method for preparing cerium carbonate powder |
| US8303918B2 (en) | 2007-03-16 | 2012-11-06 | Lg Chem, Ltd. | Method for preparing cerium carbonate powder using urea |
| JP5695068B2 (en) * | 2010-09-30 | 2015-04-01 | Hoya株式会社 | Method for manufacturing glass substrate for information recording medium and method for manufacturing information recording medium |
| CN104310456B (en) * | 2014-10-14 | 2017-03-01 | 瑞科稀土冶金及功能材料国家工程研究中心有限公司 | A kind of production method of the low chlorine root carbonated rare earth of fine granularity |
| CN106219589B (en) * | 2016-07-28 | 2017-09-15 | 乐山沃耐稀电子材料有限公司 | A kind of production technology of low-sulfur cerium hydroxide |
| RU2693176C1 (en) * | 2018-12-28 | 2019-07-01 | Общество С Ограниченной Ответственностью "Лаборатория Инновационных Технологий" | Method of producing carbonates of rare-earth elements |
| CN111392758A (en) * | 2020-03-12 | 2020-07-10 | 淄博冠海工贸有限公司 | Clean preparation method of nano-micro rare earth material |
| CN115159558B (en) * | 2022-07-05 | 2023-10-03 | 冕宁县新盛源新材料科技有限公司 | Precipitation method of rare earth carbonate |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4497785A (en) * | 1983-11-18 | 1985-02-05 | Union Oil Company Of California | Production of rare earth compounds |
| DD292216A5 (en) * | 1986-04-04 | 1991-07-25 | Stickstoffwerke Ag Wittenerg-Piesteritz, | METHOD FOR DISCONTINUOUS PRODUCTION OF RARE DCARBONATES |
| DD298763A5 (en) * | 1990-05-25 | 1992-03-12 | Stickstoffwerke Ag Wittenberg-Piesteritz,De | METHOD FOR SEPARATING THE CERTAIN FROM RARE SALT SOLUTIONS |
-
1993
- 1993-11-24 JP JP5293169A patent/JP2786095B2/en not_active Expired - Fee Related
-
1994
- 1994-11-19 EP EP94118251A patent/EP0654445A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07144915A (en) | 1995-06-06 |
| EP0654445A1 (en) | 1995-05-24 |
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